1. Technical Field
The present invention generally relates to circuit repairing, in particular, to a method for repairing a chip and a stacked structure of chips.
2. Background
In the past, a spare has to be used for repairing a system on chip (SoC), and the spare refers to replicating a backup circuit block with the same function on the same chip. When it is acquired that a function of an original circuit block is failed from an inspection result of the SoC, the backup circuit block is started and replaces the original circuit block. Thus, besides that a memory is regularly combined by a plurality of units with the same function, and that the memory may be easily replicated and shared, spares of any other logics on the SoC usually cost a lot. Without a spare, the complete chip will become useless and have to be discarded when the original circuit block is failed.
Currently, a stacked structure of chips has already been widely discussed, in which chips with different functions or different manufacturing technologies may be integrated by distributing stacked chips in a vertical direction, different from that a complete system is integrated in a single chip in the past. A semiconductor stacked structure is disclosed in U.S. Pat. No. 5,946,545. In the structure, a control chip is disposed on a chip to manage a manner of connecting stacked chips. A backup control chip is used to manage the use of backup of the stacked chips in a programmed manner, or a fuse is embedded in the control chip directly without a backup control chip to manage the use of backup of the stacked chips in a programmed manner. In the semiconductor stacked structure, the control chip and a programmed circuit (a backup control chip or a fuse) manages a backup circuit or a backup chip within the stacked chips through a through silicon via (TSV), so as to repair the chip. However, the semiconductor stacked structure is only applicable to chips normally connected, that is, each chip in the stack has to be normal. Otherwise, when the backup circuit or the backup chip is failed, the complete chip stack may be totally useless and have to be discarded.